Ingredients

The following ingredients have 4 Servings
  • Cupcakes:
  • 4 egg whites (room temperature)
  • 1 cup of white granulated sugar
  • 1 tsp vanilla extract
  • ½ cup of vegetable oil
  • 2 cups of flour
  • 1 tsp baking powder
  • ½ tsp baking soda
  • 1/8 tsp salt
  • 1 cup of buttermilk
  • Zest of 3 key limes
  • Blueberry Sauce:
  • 1/2 pint blueberries
  • 1/2 cup sugar
  • 1 tsp lemon juice
  • Frosting:
  • 8 oz cream cheese (room temperature)
  • ½ cup of butter (room temperature)
  • 2 Tbsp blueberry sauce
  • 1½ cup powder sugar

Instruction

  • Blueberry Sauce:
  • Add blueberries into a small sauce pot, heating over medium heat.
  • Add lemon juice and sugar. Stir well.
  • Cover (leaving a crack for the steam to escape) and cook for about 15 minutes, stirring often. (Watch it closely, it may over-run.)
  • Strain off some juice (about 3 Tbsp) for topping the cupcakes and puree the rest in a blender.
  • Cupcakes:
  • Preheat the oven to 350 and line a muffin pan with cupcake liners.
  • Sift flour, baking soda, salt and baking powder together and set aside.
  • Make sure your other ingredients are ready.
  • In a bowl of an electric mixer (use paddle attachment), beat egg whites for a few seconds and slowly start pouring in sugar. Beat for 3-4 minutes, until white and fluffy.
  • Start pouring in oil, slowly, as the eggs are still beating on medium-high.
  • Add vanilla and lower the speed to low.
  • Alternating, add flour mixture and buttermilk in two parts. Mix until just combined.
  • Add key lime zest. Make sure to scrape sides and bottom of the bowl and mix until all incorporated.
  • Divide batter among the cupcake cups, filling them about 2/3 of the day.
  • Bake for 18-20 minutes.
  • Cool completely before frosting!
  • Frosting:
  • Beat butter and cream cheese together, on medium-high speed, until smooth, 1-2 minutes.
  • Lower the speed to low and beat in powder sugar and blueberry sauce.
  • Turn up the speed back to medium-high and beat for about 3-4 minutes, until the frosting is light, smooth and fluffy.
  • Frost the cupcakes and drizzle blueberry sauce that you've set aside on each cupcake.